Funding is requested in this proposal to support interrelated studies on Alzheimer's disease and dementia in the People's Republic of China, using a complex, multi-phasic, and historically unprecedented epidemiologic dataset, collected in Shanghai over a period of two years (1987-88) by a multi-disciplinary team of investigators including the P.I. As of this writing, at least seven papers have been published from this dataset in refereed scientific journals. This is the first time that funding is being requested to do further data analyses on various aspects of the dataset that have not yet been analyzed nor published. In response to NIA's ongoing program announcement, this team of investigators propose to conduct several studies under the following broad topics: (1) the epidemiology of, and the identification of risk factors for, dementia and Alzheimer's disease in Chinese context; (2) the evaluation of the specificity, sensitivity, reliability and validity of diverse screening and diagnostic assessment procedures and instruments used in our study; and (3) the characterization of the sampling procedure used in the Shanghai epidemiologic survey and determination of its cost-effectiveness vis-a-vis other traditional approaches. Although several studies are proposed here, they share only one single overriding research objective: What is the epidemiology of Alzheimer's disease and related dementias in later life in the People's Republic of China--using Shanghai as a data collection point? To answer this question, the investigators are sensitive to a host of issues concerning the effect of sample design on the estimation of rates, and the sensitivity, specificity, validity, reliability and cross-cultural applicability of instruments used to determine caseness in a society where the language and culture is drastically different from the West where these instruments were originally developed. This research problem has broad implications for basic research into the etiology of Alzheimer's disease and related dementias, as well as practical clinical use. The requested funding is intended for use in the following ways: (1) to release the time of these researchers and advanced students from competing demands for teaching, administration, and clincal work; and (2) to produce a critical mass of substantive findings from the present study in order to provide other researchers in the area of aging a useful knowledge base from which to develop future investigations. The first 12-month budget requested is 258,666. The total budget requested over three years is $818,349.